Event ID - 210

Event Id210
SourceMSExchangeMTA
DescriptionAn internal MTA error occurred. Content conversion for message <message id> failed. Conversion error: <error code>, Object at fault: <object name>, Original content type: <object type>, New content type: <object type>. PDU dump reference <value> [<value> <value> <value> <value>] (14)
Event InformationAccording to Microsoft:
CAUSE:
This error will occur when the remote MTA is configured to send all message content as a General Text Body Part and sends a message containing only IA5 characters. This configuration is possible with the DEC MRX product.
Inbound, the MTA checks for the presence of 6 and 100, and if it has both, it then uses the ISO8859-1 tables to do the conversion, otherwise an NDR message is sent with invalid content type because no support for other character sets exists.
RESOLUTION:
A possible workaround is to configure the remote MTA so that it does not send all messages as General Text Body Part.
This fix allows Microsoft Exchange to accept General Text Body Part with the following registered character sets {C0,G0} == {1,6}.
To resolve this problem, obtain the hotfix mentioned below.
Reference LinksXCON: MTA Doesnt Accept IA5 in General Text Body Part

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